Inkjet recording element

ABSTRACT

The present invention relates to an ink jet recording element having very good dye keeping properties in time. Said recording element comprises a support and at least one ink-receiving layer, said ink-receiving layer comprising at least one hydrosoluble binder and at least one aluminosilicate polymer obtainable by a preparation method consisting in treating an aluminum halide with a mixture of at least one silicon alkoxide only having hydrolyzable substituents and at least one silicon alkoxide having a non-hydrolyzable substituent, with an aqueous alkali in the presence of silanol groups, the aluminum concentration being maintained less than 0.3 mol/l, the Al/Si molar ratio being maintained between 1 and 3.6 and the alkali/Al molar ratio being maintained between 2.3 and 3; and then stirring the resulting mixture at ambient temperature in the presence of silanol groups for long enough to form the hybrid aluminosilicate polymer.

FIELD OF THE INVENTION

The present invention relates to an ink jet recording element.

DESCRIPTION RELATIVE TO THE PRIOR ART

Digital photography has been growing fast for several years; the generalpublic now having access to efficient and reasonably priced digitalcameras. Therefore people are seeking to be able to produce photographicprints from a simple computer and its printer, with the best possiblequality.

Many printers, especially those linked to personal office automation,use the inkjet printing technique. There are two major families ofinkjet printing techniques: continuous jet and drop-on-demand.

Continuous jet is the simpler system. Pressurized ink (3.10⁵ Pa) isforced to go through one or more nozzles so that the ink is transformedinto a flow of droplets. In order to obtain the most regular possiblesizes and spaces between drops, regular pressure pulses are sent usingfor example a piezoelectric crystal in contact with the ink with highfrequency (up to 1 MHz) alternating current (AC) power supply. So that amessage can be printed using a single nozzle, every drop must beindividually controlled and directed. Electrostatic energy is used forthis: an electrode is placed around the ink jet at the place where dropsform. The jet is charged by induction and every drop henceforth carriesa charge whose value depends on the applied voltage. The drops then passbetween two deflecting plates charged with the opposite sign and thenfollow a given direction, the amplitude of the movement beingproportional to the charge carried by each of the plates. To preventother drops from reaching the paper, they are left uncharged: so,instead of going to the support they continue their path without beingdeflected and go directly into a container. The ink is then filtered andcan be reused.

The other category of inkjet printer is drop-on-demand (DOD). Thisconstitutes the base of inkjet printers used in office automation. Withthis method, the pressure in the ink cartridge is not maintainedconstant but is applied when a character has to be formed. In onewidespread system there is a row of 12 open nozzles, each of them beingactivated with a piezoelectric crystal. The ink contained in the head isgiven a pulse: the piezo element contracts with an electric voltage,which causes a decrease of volume, leading to the expulsion of the dropby the nozzle. When the element resumes its initial shape, it pumps inthe reservoir the ink necessary for new printings. The row of nozzles isthus used to generate a column matrix, so that no deflection of the dropis necessary. One variation of this system consists in replacing thepiezoelectric crystals by small heating elements behind each nozzle. Thedrops are ejected following the forming of bubbles of solvent vapor. Thevolume increase enables the expulsion of the drop. Finally, there is apulsed inkjet system in which the ink is solid at ambient temperature.The print head thus has to be heated so that the ink liquefies and canprint. This enables rapid drying on a wider range of products thanconventional systems.

There now exist new “inkjet” printers capable of producing photographicimages of excellent quality. However, they cannot supply good proofs ifinferior quality printing paper is used. The choice of printing paper isfundamental for the quality of obtained image. The printing paper mustcombine the following properties: high quality printed image, rapiddrying after printing, good dye keeping in time, smooth appearance andhigh gloss.

In general, the printing paper comprises a support coated with one ormore layers according to the properties required. It is possible, forexample, to apply on a support a primary attachment layer, an absorbentlayer, an ink fixing layer and a protective layer or surface layer toprovide the glossiness of the recording element. The absorbent layerabsorbs the liquid part of the water-based ink composition aftercreation of the image. Elimination of the liquid reduces the risk of inkmigration to the surface. The ink fixing layer prevents any ink lossinto the fibers of the paper base to obtain good color saturation whilepreventing excess ink that would encourage the increase in size of theprinting dots and reduce the image quality. The absorbent layer andfixing layer can also constitute a single ink-receiving layer ensuringboth functions. The protective layer is designed to ensure protectionagainst fingerprints and the pressure marks of the printer feed rollers.The ink-receiving layer usually comprises a binder, a receiving agentand various additives. The purpose of the receiving agent is to fix thedyes in the printing paper. The best-known inorganic receivers arecolloidal silica or boehmite. For example, the European PatentApplications EP-A-976,571 and EP-A-1,162,076 describe recording elementsin which the ink-receiving layer contains as inorganic receivers Ludox™CL (colloidal silica) marketed by Grace Corporation or Dispal™(colloidal boehmite) marketed by Sasol. However, printing papercomprising an ink-receiving layer containing such inorganic receiverscan have poor image stability in time, which is demonstrated by a lossof color density.

To meet the new requirements of the market in terms of photographicquality, printing speed and color stability, it is necessary to offer anew ink jet recording element having the properties as defined above,more particularly good dye keeping in time as well as a high gloss.

SUMMARY OF THE INVENTION

The new ink jet recording element according to the present inventioncomprises a support and at least one ink-receiving layer, and ischaracterized in that said ink-receiving layer comprises at least onehydrosoluble binder and at least one hybrid aluminosilicate polymerobtainable by a preparation method that comprises the following steps:

-   -   a) treating a mixed aluminum and silicon alkoxide of which the        silicon has both hydrolyzable substituents and a        non-hydrolyzable substituent, or a mixed aluminum and silicon        precursor resulting from the hydrolysis of a mixture of aluminum        compounds and silicon compounds only having hydrolyzable        substituents and silicon compounds having a non-hydrolyzable        substituent, with an aqueous alkali, in the presence of silanol        groups, the aluminum concentration being maintained at less than        0.3 mol/l, the Al/Si molar ratio being maintained between 1 and        3.6 and the alkali/Al molar ratio being maintained between 2.3        and 3;    -   b) stirring the mixture resulting from step a) at ambient        temperature in the presence of silanol groups long enough to        form the hybrid aluminosilicate polymer; and    -   c) eliminating the byproducts formed during steps a) and b) from        the reaction medium.

Throughout the present description, the expression “non-hydrolyzablesubstituent” means a substituent that does not separate from the siliconatom during the process and in particular at the time of treatment withthe aqueous alkali. Such substituents are for example hydrogen, fluorideor an organic group. On the contrary, the expression “hydrolyzablesubstituent” means a substituent eliminated by hydrolysis in the sameconditions.

In the following, the expression “modified mixed aluminum and siliconalkoxide” means a mixed aluminum and silicon alkoxide in which thealuminum atom only has hydrolyzable substituents and the silicon atomhas both hydrolyzable substituents and a non-hydrolyzable substituent.

Similarly, the expression “modified mixed aluminum and siliconprecursor” means a precursor obtained by hydrolysis of a mixture ofaluminum compounds and silicon compounds only having hydrolyzablesubstituents and silicon compounds having a non-hydrolyzablesubstituent. This is the non-hydrolyzable substituent that will be foundagain in the hybrid aluminosilicate polymer material useful in thepresent invention.

More generally, an “unmodified” compound is a compound that onlyconsists of hydrolyzable substituents and a “modified” compound is acompound that consists of a non-hydrolyzable substituent.

The ink jet recording element according to the present invention hasimproved dye keeping properties in time as well as a good gloss comparedwith the ink jet recording elements available on the market.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 to 3 represent the spectra obtained by Raman spectroscopy of thealuminosilicate polymers used for comparative purposes and used in thepresent invention.

FIGS. 4 to 12 represent the percentage of color density loss for variouscomparative ink jet recording elements and according to the presentinvention when exposed to ozone.

DETAILED DESCRIPTION OF THE INVENTION

The ink jet recording element according to the present inventioncomprises firstly a support. This support is selected according to thedesired use. It can be a transparent or opaque thermoplastic film; inparticular a film based on polyester, polymethylmetacrylate, celluloseacetate, or polyvinyl chloride, and any other appropriate material. Thesupport used in the invention can also be paper, both sides of which maybe covered with a polyethylene layer. When the support comprising thepaper pulp is coated on both sides with polyethylene, it is called ResinCoated Paper (RC Paper) and is marketed under various brand names. Thistype of support is especially preferred to constitute an inkjetrecording element. The side of the support that is used can be coatedwith a very thin layer of gelatin or another composition to ensure theadhesion of the first layer on the support.

The ink jet recording element according to the invention then comprisesat least one ink-receiving layer comprising at least one hydrosolublebinder. Said hydrosoluble binder can be gelatin or polyvinyl alcohol.The gelatin is that conventionally used in the photographic field. Sucha gelatin is described in Research Disclosure, September 1994, No.36544, part IIA Research Disclosure is a publication of Kenneth MasonPublications Ltd., Dudley House, 12 North Street, Emsworth, HampshirePO10 7DQ, United Kingdom. The gelatin can be obtained from SKW and thepolyvinyl alcohol from Nippon Gohsei, or Air Product under the nameAirvol® 130.

According to the present invention, the ink-receiving layer comprises,as receiving agent, at least one hybrid aluminosilicate polymerobtainable by a preparation method comprising the following steps:

-   -   a) treating a mixed aluminum and silicon alkoxide of which the        silicon has both hydrolyzable substitents and a non-hydrolyzable        substituent, or a mixed aluminum and silicon precursor resulting        from the hydrolysis of a mixture of aluminum compounds and        silicon compounds only having hydrolyzable substituents and        silicon compounds having a non-hydrolyzable substituent, with an        aqueous alkali, in the presence of silanol groups, the aluminum        concentration being maintained at less than 0.3 mol/l, the Al/Si        molar ratio being maintained between 1 and 3.6 and the alkali/Al        molar ratio being maintained between 2.3 and 3;    -   b) stirring the mixture resulting from step a) at ambient        temperature in the presence of silanol groups long enough to        form the hybrid aluminosilicate polymer, and    -   c) eliminating the byproducts formed during steps a) and b) from        the reaction medium.

According to one embodiment, the modified mixed aluminum and siliconprecursor can be formed in situ by mixing in aqueous medium (i) onecompound selected from the group consisting of aluminum salts, aluminumalkoxides and aluminum halogenoalkoxides and (ii) at least one compoundselected from the group consisting of unmodified silicon alkoxides andchloroalkoxides, and (iii) at least one compound selected from the groupconsisting of modified silicon alkoxides and chloroalkoxides.

The modified or unmodified alkoxide radical of the aluminum compound orsilicon compound preferably contains 1 to 5 carbon atoms, such asmethoxide, ethoxide, n-propoxide, or i-propoxide.

Preferably, an aluminum salt is used, such as a halide (e.g. chloride orbromide), a perhalogenate, a sulfate, a nitrate, a phosphate or acarboxylate. An aluminum halide, such as chloride, is particularlypreferred.

Preferably, silicon compounds are used in the form of alkoxides.

A single unmodified silicon alkoxide or a mixture of unmodified siliconalkoxides, or a single unmodified silicon chloroalkoxide or a mixture ofunmodified silicon chloroalkoxides, or a mixture of unmodified siliconalkoxides and chloroalkoxides can be used. Similarly, a single modifiedsilicon alkoxide or a mixture of modified silicon alkoxides, or a singlemodified silicon chloroalkoxide or a mixture of modified siliconchloroalkoxides, or a mixture of modified silicon alkoxides andchloroalkoxides can be used.

Preferably, a mixture (i) of an aluminum halide and (ii) a mixture withat least one unmodified silicon alkoxide and at least one modifiedsilicon alkoxide is produced.

An unmodified silicon alkoxide can be represented by the formulaSi—(OR)₄, and a modified silicon alkoxide can be represented by theformula R′—Si—(OR)₃,

wherein

-   -   R represents an alkyl group comprising 1 to 5 carbon atoms    -   R′ represents H, F, or a substituted or unsubstituted linear or        ramified alkyl or alkenyl group, comprising 1 to 8 carbon atoms,        e.g. a methyl, ethyl, n-propyl, n-butyl, 3-chloropropyl group,        or a vinyl group.

Preferably, the unmodified silicon alkoxide is tetramethyl or tetraethylorthosilicate, and the modified silicon alkoxide ismethyltriethoxysilane or vinyltriethoxysilane.

The ratio of unmodified silicon alkoxide to modified silicon alkoxide isbetween 0.1 and 10 in moles of silicon, and is preferably about 1.

In practice, the unmodified silicon alkoxide and modified siliconalkoxide mixture is first produced pure or diluted in a co-solvent suchas an alcohol. Said alcohol is preferably ethanol, used in sufficientamount to obtain a clear homogeneous mixture once the silicon compoundsare mixed with the aluminum compound. Then, this mixture is added to thealuminum salt in aqueous solution, with sting, at ambient temperaturebetween 15° C. and 35° C., preferably between 20° C. and 25° C., until aclear homogeneous mixture is obtained. A modified mixed aluminum andsilicon precursor is thus obtained. The stirring time varies from 10 to240 minutes, and is preferably 120 minutes.

According to step a) of the method for preparing the hybridaluminosilicate polymer useful in the present invention, the precursoror a modified mixed aluminum and silicon alkoxide is then put in contactwith an aqueous alkali, the aluminum concentration being maintained atless than 0.3 mol/l, the Al/Si molar ratio being maintained between 1and 3.6, and the alkali/Al molar ratio being maintained between 2.3 and3. Advantageously, the aluminum concentration is between 1.4×10⁻² and0.3 mol/l and even more preferably between 4.3×10⁻² and 0.3 mol/l.Preferably, the Al/Si molar ratio is between 1 and 2.

Preferably, an aqueous solution of sodium, potassium or lithiumhydroxide, diethylamine or triethylamine with a concentration between0.5 M and 3 M, and preferably 3 M is used. The alkali can also be in theform of an hydroalcoholic solution.

The alkali is added to the precursor or to the modified mixed aluminumand silicon alkoxide at a rate preferably between 50 and 650mmoles/hour.

The alkali in step a) is added in the presence of silanol groups. Thesegroups can be supplied by glass or silica (glass wool) particles orbeads, which have superficial hydroxy groups. When the volume of liquidto be treated is large, it may be desirable to increase the quantity ofbeads. The diameter of the beads can be between 0.2 and 5 mm andpreferably between 1 and 3 mm. To simplify the implementation of themethod for preparing the hybrid aluminosilicate polymer useful in thepresent invention, the preparation of the mixed aluminum and siliconprecursor can also be performed in the presence of silanol groups, forexample by circulating the mixture in a bed of glass beads.

After the addition of the alkali, step b) of the method for preparingthe hybrid aluminosilicate polymer useful in the present inventionconsists in stirring the mixture resulting from step a) at ambienttemperature in the presence of silanol groups long enough to form thesaid hybrid aluminosilicate polymer.

Then, step c) of the method for preparing the hybrid aluminosilicatepolymer useful in the present invention consists in eliminating from thereaction medium the byproducts formed during steps a) and b), such asthe residual ions coming essentially from the alkali used in step a).The residual ions can be eliminated by washing, by successivesedimentation or by diafiltration. The hybrid aluminosilicate polymermaterial resulting from step c) can then be concentrated bycentrifugation or nanofiltration. The introduction of non-hydrolyzablesubstituents, such as organic functions, enables providing for examplean organophilic character to the resulting hybrid aluminosilicatepolymers.

In a first embodiment of the method for preparing the hybridaluminosilicate polymer useful in the present invention, during step a)a quantity of alkali is added in order to obtain an alkali/Al molarratio of about 2.3. In this case the pH is maintained between 4 and 5,and preferably between 4.2 and 4.3. Then step b) as described above isapplied. The hybrid aluminosilicate polymer usefull in the presentinvention is thus obtained as a dispersion. Step c) to eliminate theresidual ions can then be performed by diafiltration, followed bynanofiltration concentration.

In a second embodiment of the method for preparing the hybridaluminosilicate polymer useful in the present invention, during step a)a quantity of alkali is added in order to obtain an alkali/Al molarratio of about 3. Then step b) as described above is applied. The hybridaluminosilicate polymer useful in the present invention is thus obtainedas a suspension. Step c) to eliminate the residual ions can then beperformed by diafiltration, followed by nanofiltration concentration,the hybrid alumino silicate polymer having been previously redispersedby adding acid, such as hydrochloric or acetic acid or a mixturethereof.

In a third embodiment, the method for preparing the hybridaluminosilicate polymer useful in the present invention comprises anadditional step d), after step b) and before step c). Said step d)consists in adding in a few minutes an additional quantity of aqueousalkali to reach an alkali/Al molar ratio of 3 if this ratio had notalready been reached during step a). The hybrid aluminosilicate polymerusefull in the present invention is thus obtained in suspension form.Step c) to eliminate the residual ions can then be performed bydiafiltration, followed by nanofiltration concentration, the hybridaluminosilicate polymer having been previously redispersed by addinghydrochloric acid. Step c) can also be performed by washing with osmosedwater by successive sedimentations, followed by centrifugationconcentration.

The hybrid aluminosilicate polymer useful in the present inventionresulting from step c) followed by concentration has physical gel form.The Al/Si molar ratio is between 1 and 3.6. Subsequent lyophilizationenables the hybrid aluminosilicate polymer useful in the presentinvention to be obtained as a powder. Such a hybrid aluminosilicatepolymer can be characterized in that its Raman spectrum comprises inspectral region 200 cm⁻¹ to 600 cm⁻¹ a wide band at 250±6 cm⁻¹, a wideintense band at 359±6 cm⁻¹, a shoulder at 407±7 cm⁻¹, and a wide band at501±6 cm⁻¹, as well as bands corresponding to the siliconnon-hydrolyzable substituent, wherein the bands linked to the siliconnon-hydrolyzable substituent can be juxtaposed with other bands. TheRaman spectrum is produced for the resulting hybrid aluminosilicatepolymer after step b) and before step c) and lyophilized.

In another embodiment, the method for preparing the hybridaluminosilicate polymer useful in the present invention comprises anadditional step e), after step c), by which at least one chelating agentof aluminum is added to the hybrid aluminosilicate polymer resultingfrom step c). Then the mixture is stirred. Subsequent evacuation byvacuum enables the hybrid aluminosilicate polymer useful in theinvention to be obtained in solid form.

Said chelating agent of aluminum can be selected from the groupconsisting of carboxylic acids, phosphonic acids, sulfonic acids,difunctional acids, their ester and anhydride components and aminoacids. Preferably, the chelating agent of aluminum is selected from thegroup consisting of HCOOH, R₁COOH wherein R₁ is selected from the groupconsisting of CH₃(CH₂)_(n), n being between to 0 and 12, CF₃, C₆H₅,(C₆H₅)₂, substituted aromatic rings as in salicylic acid, C₄H₄S;R₂PO(OH)₂ wherein R₂ is selected from the group consisting of CH₃, C₆H₅;R₃SO₃H wherein R₃ is CH₃(CH₂)_(n), n being between to 0 and 5;HOOC(CH₂)_(n)COOH, n=0-8; aromatic difunctional acids as phtalic acid;HOOC(CH₂)_(n)PO(OH)₂, n=2, 4; hydroxy aliphatic acids;HOOC(CH₂OH)_(n)COOH, n=1-2; CH₃CH(NH₂)COOH. Preferably, the chelatingagent is acetic acid.

The useful solvent of chelating agent of aluminum is generally water butanother solvent miscible to water can be used in order to solubilize thechelating agent before its adding to the hybrid aluminosilicate polymerresulting from step c).

Step e) can be applied directly on the hybrid aluminosilicate polymerresulting from step c) to prepare a hybrid aluminosilicate polymerresulting from step e) or when a coating composition for the preparationof the ink-receiving layer is prepared by using a hybrid aluminosilicatepolymer resulting from step c).

Step e) can comprise a first adding of acetic acid and a followingadding of another different chelating agent of aluminum. This method isparticularly useful to help the chelation when the chelating agentcomprises large bulky groups.

The amount of chelating agent of aluminum in the ink-receiving layercorresponds to a molar ratio between the chelating functions of thechelating agent and aluminum of the hybrid aluminosilicate polymer,which can be greater than 0.1 and preferably comprised between 0.1 and4.

The introduction of a chelating agent of aluminum allows to modify thesurface of the hybrid aluminosilicate polymer by forming a chelatecompound. The functional group of the chelating agent allows to increasethe affinity of the hybrid aluminosilicate polymer with the medium inwhich it is used.

The Raman spectrum of the hybrid aluminosilicate polymer materialresulting from step e) comprises the same bands as the hybridaluminosilicate polymer material resulting from step b), as well asbands corresponding to the chelating agent in its chelate form. Thehybrid aluminosilicate polymer useful in the present invention resultingfrom step e) has physical gel form. The Al/Si molar ratio is between 1and 3.6.

The ink-receiving layer comprises from 5 to 95 percent by weight ofhybrid aluminosilicate polymer compared with the total weight of the drystate ink-receiving layer.

The present invention also relates to the composition intended to becoated on the support to constitute the ink-receiving layer of therecording element described above. To produce this composition, thehydrosoluble binder is diluted in water to adjust its viscosity andfacilitate its coating. The composition then has the form of an aqueoussolution or a dispersion containing all the necessary components. Whenthe hybrid aluminosilicate polymer as described above is used forpreparing the composition as a powder, this powder must be very fine.

The composition can also comprise a surfactant to improve its coatingproperties. The composition can be coated on the support according toany appropriate coating method, such as blade, knife or curtain coating.The composition is applied with a thickness between approximately 100 μmand 200 μm in the wet state. The composition forming the ink-receivinglayer can be applied to both sides of the support. It is also possibleto provide an antistatic or anti-winding layer on the back of thesupport coated with the ink-receiving layer.

The ink jet recording element according to the invention can comprise,besides the ink-receiving layer described above, other layers havinganother function, arranged above or below said ink-receiving layer. Theink-receiving layer as well as the other layers can comprise all theother additives known to those skilled in the art to improve theproperties of the resulting image, such as UV ray absorbers, opticalbrightening agents, antioxidants, plasticizers, etc.

The ink-receiving layer useful in the present invention has a thicknessgenerally between 5 μm and 50 μm in the dry state. The ink jet recordingelement comprising such an ink-receiving layer has improved dye keepingproperties in time as well as gloss. It can be used for any type ofinkjet printer as well as for all the inks developed for thistechnology.

The following examples illustrate the present invention without howeverlimiting the scope.

1) Preparing Various Aluminosilicates

EXAMPLE 1

An aluminosilicate polymer in hollow sphere form was prepared accordingto the method described in U.S. Pat. No. 6,254,845.

Sodium orthosilicate was dissolved in purified water to obtain 50 ml ofan aqueous solution at 0.1 mol/l. Separately, aluminum chloride wasdissolved in purified water to obtain 67.15 ml of an aqueous solution at0.1 mol/l. The aluminum chloride solution was mixed at high speed withthe aqueous solution of sodium orthosilicate. At this stage, thealuminum concentration was 5.7×10⁻² mol/l. The Al/Si molar ratio was1.34. The mixture was stirred for one hour at ambient temperature. Asuspension was obtained that was filtered using a membrane filter toeliminate byproducts such as sodium chloride. The retentate that adheredto the filter was recovered, and 120 ml of purified water was added toit. The mixture was dispersed using ultrasound for one hour and thenwarmed for five days at 80° C., washed with purified water, and dried innormal conditions of temperature and pressure, and then lyophilized. Analuminosilicate polymer was obtained in hollow spherical particle form.This polymer was identified by its Raman signature or spectrumrepresented by FIG. 1.

In all the examples described, a Raman Bruker RFS 100 spectrometer(laser exciting wavelength, 1064 nm, power 800 mW and 512 scans) wasused to obtain the Raman spectra. The spectra were acquired inreflection mode (180°) using a lens with semi-cylindrical mirror.Samples were analyzed in solid form (obtained by lyophilization) withoutspecial preparation. The Raman spectrum instead of infrared spectrum waspreferred, because the materials used in the present invention werewater rich and the infrared spectrum of the material was then masked bythe water. This problem did not appear with the Raman spectratechnology. Materials that have the same Raman signature belong to thesame family.

EXAMPLE 2

0.45 moles AlCl₃, 6H₂O were added to 10 l osmosed water. Separately, amixture of tetraethyl orthosilicate and methyltriethoxysilane wasprepared in a quantity corresponding to 0.25 moles silicon and so as tohave a ratio of tetraethyl orthosilicate to methyltriethoxysilane of 1in moles silicon. This mixture was added to the aluminum chloridesolution. The resulting mixture was stirred and circulatedsimultaneously through a bed formed of 100 g glass beads 2-mm diameterusing a pump with output 8 l/min. The operation of preparing themodified mixed aluminum and silicon precursor took 60 minutes. Then,according to step a) of the method for preparing the hybridaluminosilicate polymer used in the present invention, 1.05 moles NaOH3M were added in two hours. The reaction medium clouded. According tostep b) of the preparation method, the mixture was stirred for 24 hours.The medium became clear. The circulation was stopped in the glass beadbed. Then, according to step d) of the preparation method, 0.3 molesNaOH 3M were added in five minutes. Aluminum concentration was 4.3×10⁻²mol/l, Al/Si molar ratio 1.8 and alkali/Al ratio 3. The hybridaluminosilicate polymer useful in the present invention was thusobtained as a suspension. FIG. 2 represents the Raman spectrum of thispolymer that was lyophilized to obtain its Raman signature.

Step c) of the preparation method consisted in leaving the resultingpolymer suspension to settle for 24 hours, then in discarding thesupernatant to recover the sediment. This sediment was washed withosmosed water by successive sedimentations to obtain a sodium level inthe supernatant less than 10 ppm. Then the sediment was centrifuged toobtain a gel with about 4 percent by weight of hybrid aluminosilicatepolymer. The resulting gel was lyophilized (20 mT, −50° C.) to obtain asolid of constant mass. The hybrid aluminosilicate polymer was thusobtained as a powder. The powder can be redispersed by adding water andacid, such as hydrochloric or acetic acid, and with mechanical stirring.

EXAMPLE 3

Example 2 was repeated using, for preparing the modified mixed aluminumand silicon precursor, a mixture of ethanol (3168 g), tetraethylorthosilicate and 3-chloropropyltriethoxysilane in a quantitycorresponding to 0.25 moles silicon and so as to have a tetraethylorthosilicate/3-chloropropyltriethoxysilane ratio of 1 in moles silicon.FIG. 3 represents the Raman spectrum of this polymer that waslyophilized to obtain its Raman signature.

EXAMPLE 4

Example 2 was repeated using, for preparing the modified mixed aluminumand silicon precursor, a mixture of ethanol (44.6 g), tetraethylorthosilicate and n-butyltrimethoxysilane in a quantity corresponding to0.25 moles silicon and so as to have a tetraethylorthosilicate/n-butyltrimethoxysilane ratio of 1 in moles silicon.

EXAMPLE 5

4.53 moles AlCl₃, 6H₂O were added to 100 l osmosed water. Separately, amixture of tetraethyl orthosilicate and methyltriethoxysilane wasprepared in a quantity corresponding to 2.52 moles silicon and so as tohave a ratio of tetraethyl orthosilicate to methyltriethoxysilane of 1in moles silicon. This mixture was added to the aluminum chloridesolution. The resulting mixture was stirred and circulatedsimultaneously through a bed formed of 1 kg glass beads 2-mm diameterusing a pump with output 8 l/min. The operation of preparing themodified mixed aluminum and silicon precursor took 120 minutes. Then,according to step a) of the method for preparing the hybridaluminosilicate polymer, 10.5 moles NaOH 3M were added in four hours.Aluminum concentration was 4.3×10⁻² mol/l, Al/Si molar ratio 1.8 andalkali/Al ratio 2.31. The reaction medium clouded. According to step b)of the preparation method, the mixture was stirred for 48 hours. Themedium became clear. The circulation was stopped in the glass bead bed.The hybrid aluminosilicate polymer used in the present invention wasthus obtained as a dispersion. Step c) of the method according to theinvention consisted in performing preconcentration by a factor of 3 bynanofiltration, then diafiltration using a Filmtec NF 2540nanofiltration membrane (surface area 6 m²) to eliminate the sodiumsalts to obtain an Al/Na rate greater than 100. The retentate resultingfrom the diafiltration by nanofiltration was concentrated to obtain agel with about 20 percent by weight of hybrid aluminosilicate polymerused in the present invention.

EXAMPLE 6

15 moles AlCl₃, 6H₂O, then 3.5 kg glass beads 2-mm diameter, were addedto 75 l osmosed water. Separately, a mixture of tetraethyl orthosilicateand methyltriethoxysilane was prepared in a quantity corresponding to8.34 moles silicon and so as to have a ratio of tetraethyl orthosilicateto methyltriethoxysilane of 1 in moles silicon. This mixture was addedto the aluminum chloride solution. The resulting mixture was stirredvigorously. The operation of preparing the modified mixed aluminum andsilicon precursor took 20 minutes to obtain a clear homogeneous medium.Then, according to step a) of the method for preparing the hybridaluminosilicate polymer used in the present invention, 45 moles NaOHdissolved in 75 liters of osmosed water were added to the reactionmedium, in 30 minutes. The reaction medium clouded. Aluminumconcentration was 0.1 mol/l, Al/Si molar ratio 1.8 and alkali/Al ratio3. According to step b) of the preparation method, the mixture wasstirred for 15 minutes. The hybrid aluminosilicate polymer was thusobtained as a suspension. Step c) of the preparation method consisted inadding 676 g HCl 37 percent first diluted to 5 liters, and stirring for150 minutes to obtain a dispersion of the hybrid aluminosilicatepolymer. The dispersion was then diafiltrated using a Filmtec NF 2540nanofiltration membrane (surface area 6 m²) to eliminate the sodiumsalts to achieve an Al/Na ratio greater than 100. The retentateresulting from the diafiltration by nanofiltration was concentrated toobtain a gel with about 20 percent by weight of hybrid aluminosilicatepolymer used in the present invention.

2) Preparation of Coating Compositions Constituting an Ink-ReceivingLayer Coated on a Support

As hydrosoluble binder polyvinylic alcohol (Gohsenol™ GH23 marketed byNippon Gohsei) diluted 9 percent in osmosed water and as receiving agentthe aluminosilicate polymers prepared according to examples 1 to 6 areused, as well as an aqueous dispersion of pyrogenated alumina(CAB-O-SPERSE® PG003 marketed by Cabot), an aqueous solution ofcolloidal silica (Ludox™ TMA marketed by Grace Corporation) and boehmite(Disperal™ HP 14/2 marketed by Sasol).

All the compositions result from mixing:

-   -   15.22 g water    -   3 g receiving agent (dry matter)    -   4 g polyvinylic alcohol.        When the receiving agent has powder form, the particles must        first be crushed finely.        3) Preparation of Ink Jet Recording Elements

To do this, a Resin Coated Paper type support was placed on a coatingmachine, first coated with a very thin gelatin layer, and held on thecoating machine by vacuum. This support was coated with a composition asprepared according to paragraph 2 using a spiral filmograph 125 μm thickThen, it was left to dry overnight at ambient air temperature (21° C.).

The resulting recording elements correspond to the examples shown inTable I below giving the receiving agent used in the ink-receivinglayer: TABLE I Recording Element Receiving agent in the ink-receivinglayer Ex 7 (comp.) Aluminosilicate prepared according to Example 1 Ex 8(inv.) Aluminosilicate prepared according to Example 2 Ex 9 (inv.)Aluminosilicate prepared according to Example 3 Ex 10 (inv.)Aluminosilicate prepared according to Example 4 Ex 11 (inv.)Aluminosilicate prepared according to Example 5 Ex 12 (inv.)Aluminosilicate prepared according to Example 6 Ex 13 (comp.)CAB-O-SPERSE ® PG003 Ex 14 (comp.) Ludox ™ TMA Ex 15 (comp.) Boehmite(Disperal ™ HP 14/2)4) Evaluating of Dye Keeping Properties in Time

To evaluate the dye keeping properties in time, a dye fading test byexposure to ozone was performed for each resulting recording element. Todo this, targets, comprising four colors (black, yellow, cyan andmagenta) were printed on each material using a Lexmark KODAK PPM 200printer and related ink. The targets were analyzed using aVannier-Photelec densitometer that measures the density of the variouscolors. Then the recording elements were placed to the dark in a roomwith controlled ozone atmosphere (60 ppb) for three weeks. Each week,any degradation of the color density was monitored using thedensitometer. If density losses were less than 10 percent, for all thecolors, it was considered that the material enables particularly stableprinting to be obtained.

FIG. 4 represents the percentage of density loss observed for theoriginal density 0.5 for the four colors of the targets after one weekfor examples 11, 12, 13 and 14. Letters K, C, M and Y represent thecolors black, cyan, magenta and yellow respectively.

It may be seen that the ink jet recording elements according to theinvention (Ex 11 and 12) have much better dye keeping properties in timethan that observed for the recording elements containing other inorganicreceiving agents available on the market (Ex 13 and 14).

FIGS. 5 to 9 represent the percentage of density loss observed for theoriginal density 0.5 for the four colors of the targets after three weekfor examples 7, 8, 9, 10 and 15 respectively. Once again, the figuresclearly demonstrate that the recording elements according to theinvention (Ex 8 to 10 corresponding to FIGS. 6 to 8) have much betterdye keeping properties than that observed for the recording elementscontaining the inorganic receiving agents available on the market (Ex 7and 15) and are stable for all the colors. However, up to 90 percentdensity loss may be observed for the colors magenta and cyan forcomparative Examples 7 and 15 corresponding to FIGS. 5 and 9.

The tests were repeated using an Epson 670 printer and the related Epsonink for the recording elements of examples 7, 11, 12 and 13. FIG. 10represents the percentage of density loss observed for the originaldensity 0.5 for the four colors of the targets after one week for saidexamples 7, 11, 12 and 13 respectively. The colors of the recordingelements according to the invention (Ex 11 and 12) are particularlystable compared with the recording elements of comparative examples 7and 13.

5) Evaluation of the Gloss

Gloss was measured for various resulting recording elements using aPicogloss 560 apparatus (60° geometry) marketed by Erichsen.

The results are given below in Table II. TABLE II Recording elementGloss (percent) Ex 7 (comp.) 2 Ex 11 (inv.) 60 Ex 12 (inv.) 55

The results of Table II show that the recording elements according tothe present invention show a good gloss, which is wanted to reproducethe gloss of photographs developed by a conventional silver process.

6) Preparation of a Coating Composition Constituting an Ink-ReceivingLayer Coated on a Support

EXAMPLE 16

Glacial acetic acid (340 mg, 5.6 mmol) was added to 20 g of a gel ofmethyl hybrid aluminosilicate polymer (Al amount=75 mg, 2.8 mmol,measured by inductively coupled plasma atomic emission spectroscopy,ICP) as obtained in Example 5. The mixture was stirred during 2 days.The excess of water and the unreacted acetic acid were removed byevacuation under vacuum at 35° C. 4.4 g of a white powder is obtained.The Raman spectrum comprises the bands of the hybrid aluminosilicatepolymer obtained in Example 5, as well as the bands corresponding to thechelating agent in its acetate form.

As hydrosoluble binder of polyvinylic alcohol (Gohsenol™ GH23 marketedby Nippon Gohsei) diluted 9 percent in osmosed water and as receivingagent the aluminosilicate polymers prepared as above were used.

The composition resulted from mixing:

-   -   10.1 gwater    -   2 g receiving agent (dry matter)    -   2.7 g polyviaylic alcohol.        When the receiving agent has powder form, the particles must        first be crushed finely. The mixture is sheared overnight.

EXAMPLE 17

1 g of the hybrid aluminosilicate polymer modified with acetic acidobtained in Example 16 (Al amount=16.2 mg, 0.6 mmole) was dispersed in10 g of water. Benzoic acid (38 mg, 0.3 mmole) was then solubilized in 1g of ethanol and added to the hybrid aluminosilicate polymer suspension.The mixture was stirred during 2 days. The excess of water was removedunder vacuum at 35° C. A white powder was obtained. The Raman spectrumcomprises the bands of the hybrid aluminosilicate polymer obtained inExample 5, as well as the bands corresponding to the chelating agent inits benzoate form and residual acetate form.

As hydrosoluble binder of polyvinylic alcohol (Gohsenol™ GH23 marketedby Nippon Gohsei) diluted 9 percent in osmosed water and as receivingagent the aluminosilicate polymers prepared as above were used.

The composition resulted from mixing:

-   -   2.91 g water    -   0.497 g receiving agent (dry matter)    -   0.708 g polyvinylic alcohol.        When the receiving agent has powder form, the particles must        first be crushed finely. The mixture is sheared overnight.

EXAMPLE 18

1 g of the hybrid aluminosilicate polymer modified with acetic acidobtained in Example 16 (Al amount=16.2 mg, 0.6 mmole) was dispersed in15 g of water. Propionic acid (181 mg, 2.5 mmole) was added to thehybrid aluminosilicate polymer suspension. The mixture was stirredduring 2 days. The excess of water and propionic acid was removed undervacuum at 35° C. A white powder was obtained. The Raman spectrumcomprises the bands of the hybrid aluminosilicate polymer obtained inExample 5, as well as the bands corresponding to the chelating agent inits propionate form and residual acetate form.

As hydrosoluble binder of polyvinylic alcohol (Gohsenol™ GH23 marketedby Nippon Gohsei) diluted 9 percent in osmosed water and as receivingagent the aluminosilicate polymers prepared as above were used.

The composition resulted from mixing:

-   -   3.11 g water    -   0.60 g receiving agent (dry matter)    -   0.83 g polyvinylic alcohol.        When the receiving agent has powder form, the particles must        first be crushed finely. The mixture is sheared overnight.

EXAMPLE 19

In this example, the chelating agent of aluminum is added when thecoating composition is prepared. As hydrosoluble binder of polyvinylicalcohol (Gohsenol™ GH23 marketed by Nippon Gohsei) diluted 9 percent inosmosed water and as receiving agent the aluminosilicate polymerprepared according to example 5 were used. The chelating agent is aceticacid.

The composition resulted from mixing:

-   -   7.93 g osmosed water    -   2.17 glacial acetic acid (36.2 mmol)    -   2 g receiving agent (dry matter, Al amount=0.49 mg, 18.2 mmol)    -   2.7 g polyvinylic alcohol.        When the receiving agent has powder form, the particles must        first be crushed finely. The mixture was sheared overnight.        7) Preparation of Ink Jet Recording Element

A Resin Coated Paper type support was placed on a coating machine, firstcoated with a very thin gelatin layer, and held on the coating machineby vacuum. This support was coated with a composition as preparedaccording to paragraph 6 using a blade. The wet thickness was 200 μm.Then, it was left to dry 3 hours at ambient air temperature (21° C.).

The resulting recording elements correspond to the examples shown inTable III below giving the receiving agent used in the ink-receivinglayer: TABLE III Recording Element Receiving agent in the ink-receivinglayer Ex 20 (inv.) Aluminosilicate prepared according to Example 16 Ex21 (inv.) Aluminosilicate prepared according to Example 17 Ex 22 (inv.)Aluminosilicate prepared according to Example 18 Ex 23 (inv.)Aluminosilicate prepared according to Example 198) Evaluation of Dye Keeping Properties in Time

The evaluation of dye keeping properties was made as in paragraph 4 forExample 23.

FIGS. 11 and 12 represent the percentage of density loss observed forthe maximum density for the four colors of the target for each week forExample 23 printed using the Lexmark Kodak PPM200 printer and relatedink and a Epson 890 printer and related ink respectively. Letter C, M, Yand K represent the colors cyan, magenta, yellow and black respectively.

The figures clearly demonstrate that the recording element according tothe invention has very good dye keeping properties.

9) Evaluation of the Gloss

Evaluation of the gloss was made as in paragraph 5 for Examples 20-23.

The results are given below in Table IV. TABLE IV Recording elementGloss (percent) Ex 20 (inv.) 30 Ex 21 (inv.) 89 Ex 22 (inv.) 90 Ex. 23(inv.) 86

The results of Table IV show that the recording elements according tothe present invention show a good gloss, which is wanted to reproducethe gloss of photographs developed by a conventional silver process.

1. An ink jet recording element comprising a support and at least oneink-receiving layer, wherein said ink-receiving layer comprises at leastone hydrosoluble binder and at least one hybrid aluminosilicate polymerobtainable by a preparation method that comprises the following steps:a) treating a mixed aluminum and silicon alkoxide of which the siliconhas both hydrolyzable substituents and a non-hydrolyzable substituent,or a mixed aluminum and silicon precursor resulting from the hydrolysisof a mixture of aluminum compounds and silicon compounds only havinghydrolyzable substituents and silicon compounds having anon-hydrolyzable substituent, with an aqueous alkali, in the presence ofsilanol groups, the aluminum concentration being maintained at less than0.3 mol/l, the Al/Si molar ratio being maintained between 1 and 3.6 andthe alkali/Al molar ratio being maintained between 2.3 and 3; b)stirring the mixture resulting from step a) at ambient temperature inthe presence of silanol groups long enough to form the hybridaluminosilicate polymer; and c) eliminating the byproducts formed duringsteps a) and b) from the reaction medium.
 2. The recording elementaccording to claim 1, wherein the alkali of step a) to prepare thehybrid aluminosilicate polymer is selected from the group consisting ofsodium, potassium, or lithium hydroxide, diethylamine, andtriethylamine.
 3. The recording element according to claim 1, whereinthe silanol groups used to prepare the hybrid aluminosilicate polymerare supplied in silica or glass bead form.
 4. The recording elementaccording to claim 1, wherein the aluminum concentration used to preparethe hybrid aluminosilicate polymer is maintained between 1.4×10−2 and0.3 mol/l.
 5. The recording element according to claim 1, wherein thealuminum concentration used to prepare the hybrid aluminosilicatepolymer is maintained between 4.3×10−2 and 0.3 mol/l.
 6. The recordingelement according to claim 1, wherein said alkali/Al molar ratio toprepare the hybrid aluminosilicate polymer is about 2.3.
 7. Therecording element according to claim 1, wherein said alkali/Al molarratio to prepare the hybrid aluminosilicate polymer is about
 3. 8. Therecording element according to claim 1, wherein the method for preparingthe hybrid aluminosilicate polymer comprises, after step b) and beforestep c), a step d), by which alkali is added in order to reach analkali/Al molar ratio of 3 if this ratio has not already been reached instep a).
 9. The recording element according to claim 1, wherein saidmixed aluminum and silicon precursor resulting from hydrolysis of amixture of aluminum compounds and silicon compounds only havinghydrolyzable substituents and silicon compounds having anon-hydrolyzable substituent is a product resulting from the mixture inan aqueous medium (i) of a compound selected from the group consistingof aluminum salts, aluminum alkoxides and aluminum halogenoalkoxides and(ii) at least one compound selected from the group consisting of siliconalkoxides and chloroalkoxides only having hydrolyzable substituents, and(iii) at least one compound selected from the group consisting ofsilicon alkoxides and chloroalkoxides having a non-hydrolyzablesubstituent.
 10. The recording element according to claim 9, whereinsaid mixed aluminum and silicon precursor is the product resulting fromthe mixture (i) of an aluminum halide and (ii) a mixture having at leastone silicon alkoxide only having hydrolyzable substituents and at leastone silicon alkoxide having a non-hydrolyzable substituent.
 11. Therecording element according to claim 10, wherein the ratio of siliconalkoxide only having hydrolyzable substituents to silicon alkoxidehaving a non-hydrolyzable substituent is between 0.1 and 10 in molessilicon.
 12. The recording element according to claim 11, wherein theratio of silicon alkoxide only having hydrolyzable substituents tosilicon alkoxide having a non-hydrolyzable substituent is 1 in molessilicon.
 13. The recording element according to claim 9, wherein thesilicon alkoxide having a non-hydrolyzable substituent is represented bythe formulaR′—Si—(OR)3 wherein R represents an alkyl group comprising 1 to 5 carbonatoms R′ represents H, F, or a substituted or unsubstituted non-linearor ramified alkyl or alkenyl group comprising 1 to 8 carbon atoms. 14.The recording element according to claim 13, wherein R′ represents amethyl, ethyl, n-propyl, n-butyl, 3-chloropropyl, or vinyl group. 15.The recording element according to claim 14, wherein said siliconalkoxide having a non-hydrolyzable substituent is methyltriethoxysilaneor vinyltriethoxysilane.
 16. The recording element according to claim10, wherein said silicon alkoxide only having hydrolyzable substituentsis tetramethyl orthosilicate or tetraethyl orthosilicate.
 17. Therecording element according to claim 1, wherein the method for preparingthe aluminosilicate polymer comprises, after step c), a step e), bywhich at least one chelating agent of aluminum is added to the hybridaluminosilicate polymer resulting from step c).
 18. The recordingelement according to claim 17, wherein step e) is applied directly onthe hybrid aluminosilicate polymer resulting from step c) to prepare ahybrid aluminosilicate polymer resulting from step e) or when a coatingcomposition for the preparation of the ink-receiving layer is preparedby using a hybrid aluminosilicate polymer resulting from step c). 19.The recording element according to claim 17, wherein said chelatingagent of aluminum is selected from the group consisting of carboxylicacids, phosphonic acids, sulfonic acids, difunctional acids, their esterand anhydride components and amino acids.
 20. The recording elementaccording to claim 19, wherein said chelating agent of aluminum isselected from the group consisting of HCOOH, R₁COOH wherein R₁ isselected from the group consisting of CH₃(CH₂)_(n), n being between to 0and 12, CF₃, C₆H₅, (C₆H₅)₂, substituted aromatic rings, C₄H₄S; R₂PO(OH)₂wherein R₂ is selected from the group consisting of CH₃, C₆H₅; R₃SO₃Hwherein R₃ is CH₃(CH₂)_(n), n being between to 0 and 5;HOOC(CH₂)_(n)COOH, n=0-8; aromatic difunctional acids;HOOC(CH₂)_(n)PO(OH)₂, n=2, 4; hydroxy aliphatic acids;HOOC(CH₂OH)_(n)COOH, n=1-2; CH₃CH(NH₂)COOH.
 21. The recording elementaccording to claim 17, wherein step e) comprises a first adding ofacetic acid and a following adding of another different chelating agentof aluminum.
 22. The recording element according to claim 17, whereinthe amount of the chelating agent in the ink-receiving layer correspondsto a molar ratio between the chelating functions of the chelating agentand aluminum of the hybrid aluminosilicate polymer, and wherein thismolar ratio is greater than 0.1.
 23. The recording element according toclaim 1, wherein said ink-receiving layer comprises between 5 and 95percent by weight of hybrid aluminosilicate polymer compared with thetotal weight of the dry ink-receiving layer.
 24. The recording elementaccording to claim 1, wherein the hydrophilic binder is gelatin orpolyvinyl alcohol.
 25. A coating composition for the preparation ofink-receiving layers for the ink jet recording element according toclaim 1.